1. Field of the Invention
This invention pertains generally to electric vehicles (EVs), and more particularly to infrastructure modifications and additions to provide capabilities for charging many EVs over a power supply grid.
2. Description of Related Art
Recent advances in battery technology and communications, information, and wireless technologies, as well as increased awareness in green energy and greenhouse gases, have resulted in dramatic innovations in electric vehicles using these technologies. Products such as the Nissan Leaf, Chevy Volt, and Ford Focus Electric are being promoted in the process of creating mass markets for electric vehicles in the United States. Electric utilities, on their part, are working towards enhancing their own infrastructures through both their own investments as well as those from the United States Department of Energy (US DOE) Stimulus Grants. These infrastructure enhancements will require massive changes in distribution as well as transmission systems.
If 25% of all vehicles were electric vehicles (EVs), the present infrastructure in the United States would be unable to support charging those EVs. Some electric utilities have reported numbers that indicate that even a single 220V charger within the circuit served by a transformer may, during peak consumption hours, overload and burn out the transformer. Therefore, the existing infrastructure needs to be upgraded both from a capacity standpoint as well as from a flexibility and power routing and control standpoint.
Adding capacity to an electric utility's infrastructure is far more expensive than adding intelligence and a smart power routing capability, and the eventual solution will likely require a smart combination of both. Certainly, adding auxiliary power sources at the edge of the power network such as residential solar photovoltaic cells (PVCs) to feed into the grid would help from a capacity standpoint, but using such alternative power sources in a smart manner so as to move the energy around to where it is needed from where it is produced will require a very smart grid.